The present invention relates generally to fuel pumps and, more particularly, to a fuel pump of a vehicle.
It is known to provide a fuel tank in a vehicle to hold fuel to be used by an engine of the vehicle. It is also known to provide a fuel pump to pump fuel from the fuel tank to the engine. One type of fuel pump is known as a high-pressure turbine fuel pump. The high-pressure turbine fuel pump typically includes an impeller rotatable between inlet and outlet plates. The impeller is of a closed vane type to improve pump efficiency and performance. The impeller has a hub portion, a plurality of blade tips extending radially from the hub portion and disposed circumferentially thereabout and a peripheral ring portion extending radially from the blade tips. However, the closed vane impeller is hampered by flow loss due to wear of a peripheral ring portion that shrouds the blade tips of the impeller.
The peripheral ring that shrouds the blade tips of the closed vane impeller improves pump performance by providing a rotational surface that aids to direct the fluid into a flow channel. The peripheral ring also functions as an axial sealing surface between the fluid pressure within the flow channel and the fluid pressure surrounding a major diameter of the impeller. When the fuel pump is operated in fuel containing concentration of abrasive contaminants, the peripheral ring can wear and result in a loss of flow.
Therefore, it is desirable to minimize the flow loss associated with axial wear of the peripheral ring portion of the impeller while maintaining performance benefits the peripheral ring portion provides in a fuel pump for a vehicle. It is also desirable to provide a fuel pump for a fuel tank in a vehicle that eliminates higher cost and process infeasible materials such as ceramic plates and impeller. It is further desirable to improve fuel pump durability using existing low cost materials and production feasible methods for a fuel pump for a fuel tank in a vehicle.
It is, therefore, one object of the present invention to provide a fuel pump for a fuel tank in a vehicle which eliminates a sealing function of a peripheral ring portion of an impeller.
It is another object of the present invention to provide a fuel pump for a vehicle that minimizes flow loss associated with axial wear of a peripheral ring portion of an impeller.
To achieve the foregoing objects, the present invention is a fuel pump for a vehicle including a pump section having a flow channel and a rotatable impeller cooperating with the flow channel to pump fuel therethrough. The fuel pump also includes a motor section disposed adjacent the pump section and having a motor to rotate the impeller. The fuel pump further includes an outlet section disposed adjacent the motor section to allow pumped fuel to exit the fuel pump. The pump section includes a mechanism for minimizing leakage of fuel from the flow channel radially.
One advantage of the present invention is that a new fuel pump is provided for a vehicle. Another advantage of the present invention is that the fuel pump uses existing low cost materials and production feasible methods. Yet another advantage of the present invention is that the fuel pump has improved fuel pump durability due to elimination of a dynamic sealing surface. Still another advantage of the present invention is that the fuel pump has improved fuel pump efficiency due to reduced friction at the impeller outside diameter surface.
Other objects, features, and advantages of the present invention will be readily appreciated, as the same becomes better understood, after reading the subsequent description taken in conjunction with the accompanying drawings.